Every year, people around the world celebrate Arbor Day, an international holiday dedicated to planting and honoring trees. This year, Mayor Eric Garcetti and Councilmember Felipe Fuentes joined City Plants in hosting Los Angeles’ own Arbor Day celebration in Sylmar, and it was a smashing success!

On days when the mercury hits 90 degrees and keeps rising, it’s almost instinctive to reach for the HVAC control. Most folks in the US, especially in warm, humid states, can’t imagine life without their air conditioning. But A/C has only been in use in private houses for the past 80 years. How did human beings beat the heat before then, and what can this teach us about environmentally friendly cooling for our homes today?